Regulatory Citation(s):

 

78.83. Surface and coal protective casing and cementing procedures.

 

(j) If it is anticipated that cement used to permanently cement the surface casing cannot be circulated to the surface a cement basket may be installed immediately above the depth of the anticipated lost circulation zone.

 

 

Question:

 

If an operator wishes to install a back-up cement basket in the event that the uppermost basket fails, what are appropriate set depths for each basket used?

 

 

Response:

 

Cement baskets are attached to the casing at pipe joints, and so the location of the first basket should be placed at the pipe joint immediately above the zone of lost circulation.  The second cement basket should be no more than one pipe section above the lowermost basket.  Placing a cement basket near the surface and leaving long sections of the surface or coal protective casing exposed to the formation is not recommended.